Vehicle control device, vehicle, method of controlling vehicle control device, and non-transitory computer-readable storage medium

ABSTRACT

This invention provides a vehicle control device for controlling a vehicle, which comprises a first detection unit configured to detect an out-of-lane region outside a lane in which the vehicle is traveling; a second detection unit configured to detect an obstacle; a guiding unit configured to start guiding the vehicle to the out-of-lane region in a case where the first detection unit detects the out-of-lane region and the second detection unit detects the obstacle; and a steering control unit configured to determine excess or deficiency of avoidance steering by a driver for avoiding a collision with the obstacle in response to the guidance by the guiding unit and perform steering assist on the basis of a degree of the excess or deficiency.

CROSS-REFERENCE TO RELATED APPLICATION(S)

This application claims priority to and the benefit of Japanese PatentApplication No. 2021-061590 filed on Mar. 31, 2021, the entiredisclosure of which is incorporated herein by reference.

BACKGROUND OF THE INVENTION Field of the Invention

The present invention relates to a vehicle control device, a vehicle, amethod of controlling the vehicle control device, and a non-transitorycomputer-readable storage medium.

Description of the Related Art

There is known a technique of controlling steering so as to avoid anobstacle in a case where the obstacle exists in front of a travelingvehicle. The technique is disclosed in, for example, Japanese PatentLaid-Open No. 2017-206040 and Japanese Patent Laid-Open No. 2019-151207.

However, occurrence of the obstacle may hinder a driver's calmoperation. In some cases, the driver may operate a steering wheel morethan necessary and the vehicle may deviate even from an adjacent lane.In a case where another obstacle exists at the position by chance, asecondary collision may occur.

SUMMARY OF THE INVENTION

An object of the present invention is to provide a technique forrestraining a vehicle from deviating from an out-of-lane region even ifthe vehicle enters the out-of-lane region in order to avoid a collisionwith an obstacle.

In order to solve the above problem, for example, a vehicle controldevice of the present invention has the following configuration. Thatis, the vehicle control device for controlling a vehicle, whichcomprises: a first detection unit configured to detect an out-of-laneregion outside a lane in which the vehicle is traveling; a seconddetection unit configured to detect an obstacle; a guiding unitconfigured to start guiding the vehicle to the out-of-lane region in acase where the first detection unit detects the out-of-lane region andthe second detection unit detects the obstacle; and a steering controlunit configured to determine excess or deficiency of avoidance steeringby a driver for avoiding a collision with the obstacle in response tothe guidance by the guiding unit and perform steering assist on thebasis of a degree of the excess or deficiency.

Further features of the present invention will become apparent from thefollowing description of exemplary embodiments with reference to theattached drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram of a vehicle and a control device according toan embodiment;

FIG. 2 is a flowchart showing processing of a lane keep mode executed bya vehicle control device;

FIG. 3 is a flowchart showing processing of a lane keep mode executed bya vehicle control device;

FIG. 4 is a flowchart showing details of S309 in FIG. 3;

FIG. 5 is an explanatory diagram illustrating traveling of a vehicle anddetails of processing in a lane keep mode in an embodiment;

FIG. 6 is an explanatory diagram illustrating traveling of a vehicle anddetails of processing in a lane keep mode in an embodiment;

FIG. 7 is an explanatory diagram illustrating a driving example at thetime of detecting an obstacle;

FIGS. 8A and 8B are explanatory diagrams of the processing in S309 ofFIG. 3; and

FIG. 9 illustrates an example of a traveling path based on a processingresult for collision avoidance.

DESCRIPTION OF THE EMBODIMENTS

Hereinafter, embodiments will be described in detail with reference tothe attached drawings. Note that the following embodiments are notintended to limit the scope of the claimed invention, and limitation isnot made an invention that requires all combinations of featuresdescribed in the embodiments. Two or more of the multiple featuresdescribed in the embodiments may be combined as appropriate.Furthermore, the same reference numerals are given to the same orsimilar configurations, and redundant description thereof is omitted.

First Embodiment

FIG. 1 is a block diagram of a vehicle V and a control device 1 thereofaccording to an embodiment of the present invention. In FIG. 1, thevehicle V is schematically illustrated in a plan view and a side view.The vehicle V is, for example, a four-wheeled sedan passenger vehicle.

The vehicle V of the present embodiment is, for example, a parallelhybrid vehicle. In this case, a power plant 50, which is a travelingdriving unit that outputs driving force for rotating driving wheels ofthe vehicle V, can include an internal combustion engine, a motor, andan automatic transmission. The motor can be used as a drive source foraccelerating the vehicle V and can also be used as a generator at thetime of deceleration or the like (regenerative braking).

<Control Device>

A configuration of the control device 1 that is an onboard device of thevehicle V will be described with reference to FIG. 1. The control device1 includes an ECU group (control unit group) 2. The ECU group 2 includesa plurality of ECUs 20 to 28 that can communicate with one another. EachECU includes a processor represented by a CPU, a storage device such asa semiconductor memory, an interface with an external device, and thelike. The storage device stores programs executed by the processor, dataused for processing by the processor, and the like. Each ECU may includea plurality of processors, storage devices, interfaces, and the like.Note that the number of ECUs and functions assigned to the ECUs can bedesigned as appropriate, and the ECUs and functions can be subdivided orintegrated, when compared with the present embodiment. Note that, inFIG. 1, names of representative functions are given to the ECUs 20 to28. For example, the ECU 20 is expressed as “driving control ECU”.

The ECU 20 executes control regarding driver assistance includingautomated driving of the vehicle V. In the automated driving, driving(acceleration or the like of the vehicle V by the power plant 50),steering, and braking of the vehicle V are automatically performedwithout necessitating a driver's operation. Further, the ECU 20 canexecute, for example, traveling assist control such as a collisionmitigation brake and lane departure prevention in manual driving. Thecollision mitigation brake issues an instruction to activate brakedevices 51 in a case where the possibility of collision with an obstacleahead increases, thereby assisting collision avoidance. The lanedeparture prevention issues an instruction to activate an electric powersteering device 41 in a case where the possibility that the vehicle Vdeviates from a lane increases, thereby assisting lane departureavoidance. The ECU 20 can execute automatic following control forcausing the vehicle V to automatically follow a preceding vehicle inboth automated driving and manual driving. In the case of automateddriving, all of acceleration, deceleration, and steering of the vehicleV may be automatically performed. In the case of manual driving,acceleration and deceleration of the vehicle V may be automaticallyperformed.

The ECU 21 is an environment recognition unit that recognizes atraveling environment of the vehicle V on the basis of detection resultsby detection units 31A, 31B, 32A, and 32B that detect a situation aroundthe vehicle V. In the present embodiment, the detection units 31A and31B are cameras that capture an image of the front of the vehicle V(hereinafter, also referred to as the camera 31A and the camera 31B) andare attached to the vehicle interior side of a windshield at the frontof a roof of the vehicle V. By analyzing the image captured by thecamera 31A, it is possible to extract a contour of a target object orextract a division line (white line or the like) of a lane on a road.

In the present embodiment, the detection unit 32A is a light detectionand ranging (LiDAR) (hereinafter, also referred to as the LiDAR 32A),detects a target object around the vehicle V, and measures a distancefrom the target object. In the present embodiment, five LiDARs 32A areprovided, including one at each corner portion of a front part of thevehicle V, one at the center of a rear part of the vehicle V, and one ateach lateral side of the rear part of the vehicle V. The detection unit32B is a millimeter-wave radar (hereinafter, also referred to as theradar 32B), detects a target object around the vehicle V, and measures adistance from the target object. In the present embodiment, five radars32B are provided, including one at the center of the front part of thevehicle V, one at each corner portion of the front part of the vehicleV, and one at each corner portion of the rear part of the vehicle V.

The ECU 22 is a steering control unit that controls the electric powersteering device 41. The electric power steering device 41 includes amechanism that steers front wheels in response to a driver's drivingoperation (steering operation) on a steering wheel ST. The electricpower steering device 41 includes a driving unit 41 a including a motorthat exerts driving force for assisting a steering operation orautomatically steering the front wheels (also referred to as steeringassist torque), a steering angle sensor 41 b, a torque sensor 41 c thatdetects torque due to steering by the driver (referred to as driversteering torque to be distinguished from steering assist torque). TheECU 22 can also acquire a detection result by a sensor 36 that detectswhether or not the driver grips the steering wheel ST and can monitorthe driver's gripping state.

Blinker levers 51 and 52 are provided in the vicinity of the steeringwheel ST. An occupant can operate left and right direction indicatorlamps (not illustrated) by operating the blinker levers 51 and 52. Inthe present embodiment, the occupant can issue an instruction onautomatic course change of the vehicle V by operating the blinker levers51 and 52. As the instruction on automatic course change, for example,the occupant can issue an instruction to change the lane to a left laneby operating the blinker lever 51 and can issue an instruction to changethe lane to a right lane by operating the blinker lever 52. Theinstruction to change the course by the occupant may be acceptableduring automated driving or automatic following control.

The ECU 23 is a braking control unit that controls a hydraulic device42. The driver's braking operation on a brake pedal BP is converted intoa hydraulic pressure in a brake master cylinder BM and is transmitted tothe hydraulic device 42. The hydraulic device 42 is an actuator that cancontrol a hydraulic pressure of hydraulic oil to be supplied to thebrake device (for example, a disc brake device) 51 provided on each ofthe four wheels on the basis of the hydraulic pressure transmitted fromthe brake master cylinder BM, and the ECU 23 performs driving control ofan electromagnetic valve and the like included in the hydraulic device42. The ECU 23 can also turn on brake lamps 43B at the time of braking.This enables the following vehicle to give more attention to the vehicleV.

The ECU 23 and the hydraulic device 42 can constitute an electric servobrake. The ECU 23 can control, for example, distribution of the brakingforce by the four brake devices 51 and the braking force by regenerativebraking of the motor included in the power plant 50. The ECU 23 can alsoachieve an ABS function, traction control, and a posture controlfunction of the vehicle V on the basis of detection results by wheelspeed sensors 38 provided for the respective four wheels, a yaw ratesensor (not illustrated), and a pressure sensor 35 that detects apressure in the brake master cylinder BM.

The ECU 24 is a stop keeping control unit that controls electric parkingbrake devices (for example, drum brakes) 52 provided on the rear wheels.Each electric parking brake device 52 includes a mechanism for lockingthe corresponding rear wheel. The ECU 24 can control locking andunlocking of the rear wheels by using the electric parking brake devices52.

The ECU 25 is an in-vehicle notification control unit that controls aninformation output device 43A that notifies the inside of the vehicle ofinformation. The information output device 43A includes, for example, adisplay device provided on a head-up display or instrument panel or asound output device. The information output device 43A may furtherinclude a vibration device. The ECU 25 causes the information outputdevice 43A to output, for example, various types of information such asa vehicle speed and an outside air temperature, information such asroute guidance, and information regarding a state of the vehicle V.

The ECU 26 includes a communication device 26 a for vehicle-to-vehiclecommunication. The communication device 26 a performs wirelesscommunication with other surrounding vehicles to exchange informationwith the vehicles.

The ECU 27 is a driving control unit that controls the power plant 50.In the present embodiment, one ECU 27 is allocated to the power plant50, but one ECU may be allocated to the internal combustion engine, themotor, and the automatic transmission. For example, the ECU 27 controlsan output of the internal combustion engine or the motor or switches agear ratio of the automatic transmission in accordance with the driver'sdriving operation, the vehicle speed, or the like detected by anoperation detection sensor 34 a provided in an accelerator pedal AP oran operation detection sensor 34 b provided in the brake pedal BP. Notethat the automatic transmission includes a rotation speed sensor 39 thatdetects the rotation speed of an output shaft of the automatictransmission as a sensor that detects a traveling state of the vehicleV. The vehicle speed of the vehicle V can be calculated on the basis ofa detection result by the rotation speed sensor 39.

The ECU 28 is a position recognition unit that recognizes a currentposition and a course of the vehicle V. The ECU 28 controls a gyrosensor 33, a GPS sensor 28 b, and a communication device 28 c andperforms information processing on a detection result or a communicationresult. The gyro sensor 33 detects a rotational motion of the vehicle V.The course of the vehicle V can be determined on the basis of thedetection result by the gyro sensor 33 and the like. The GPS sensor 28 bdetects the current position of the vehicle V. The communication device28 c performs wireless communication with a server that provides mapinformation and traffic information and acquires these pieces ofinformation. A database 28 a can store high accuracy map information,and thus the ECU 28 can specify the position of the vehicle V in a lanewith higher accuracy on the basis of the map information and the like.

An input device 45 is disposed inside the vehicle so as to be operatedby the driver and accepts an input of an instruction or information fromthe driver.

<Control Example>

A driving control mode of the vehicle V includes an automated drivingmode and a manual driving mode selectable by an operation of theoccupant. The automated driving mode includes a lane keep assist systemmode (LKAS mode) in which the vehicle V is kept in a lane in which thevehicle is traveling. When the driver performs an operation to turn onthe LKAS mode via the input device 45, the ECU 20 performs drivingcontrol according to the LKAS mode. A main point of the presentembodiment is collision avoidance processing at the time of detecting anobstacle during traveling in the LKAS mode. Therefore, description ofthe manual driving mode is omitted.

Hereinafter, processing of the ECU 20 during traveling in the LKAS modewill be described. The flowcharts in FIGS. 2 to 4 show a processingprocedure of the ECU 20 during traveling in the LKAS mode according tothe embodiment.

In S201, the ECU 20 determines whether or not the driver has operatedthe blinker lever 51 or 52. The operation on the blinker lever 51 or 52can be regarded as an active expression of the driver's intention toturn right, turn left, or change the lane to an adjacent lane.Therefore, the ECU 20 advances the processing to S207, turns off theLKAS mode, and terminates the present processing (switches to the manualdriving mode).

In a case where the blinker lever 51 or 52 is not operated, in S202, theECU 20 determines whether or not a distance between a lane boundary lineand the vehicle V (in the embodiment, a center position between both thefront wheels of the vehicle V) is equal to or less than a presetthreshold. In a case where the distance is equal to or less than thethreshold, the ECU 20 performs an assist operation for warning thedriver in S203. For example, the ECU 20 controls the information outputdevice 43A to display a warning message and make an alarm sound.Alternatively, a warning notification may be issued by energizing adriving unit (not illustrated) to vibrate the steering wheel ST or thelike.

In S204, the ECU 20 determines whether or not the vehicle V has crossedthe lane boundary line. A threshold used in the determination in S204only needs to be a value smaller than the threshold used in S202described above. In a case where it is determined that the vehicle V hascrossed the lane boundary line, the ECU 20 advances the processing toS207, turns off the LKAS mode, and terminates the present processing.

In S205, the ECU 20 recognizes lane division lines on both sides of thelane in which the vehicle is traveling on the basis of information fromthe ECU 21 (cameras 31A and 31B), calculates a path passing through thecenter of the lane as a target path, and updates a previously calculatedtarget path.

Then, in S206, a deviation amount of the calculated target path from thecurrent vehicle V is obtained. Then, the ECU 20 controls the ECU 22 sothat the deviation amount falls within an allowable range. The ECU 22controls steering under the control of the ECU 20.

Next, in S208, the ECU 20 determines whether or not there is a laneadjacent to the lane in which the vehicle is traveling on the basis ofthe information from the ECU 21 (cameras 31A and 31B). In a case whereit is determined that there is an adjacent lane, in S209, the ECU 20calculates a traveling path in the adjacent lane and updates apreviously calculated traveling path in the adjacent lane (if itexists).

In S210, the ECU 20 determines whether or not there is an obstacle(typically, a person) ahead in the lane in which the vehicle istraveling on the basis of the information from the ECU 21 (cameras 31Aand 31B). If not, the ECU 20 returns the processing to S201 and repeatsthe processing in S201.

Herein, specific control processing by the ECU 20 in the LKAS mode willbe described with reference to FIGS. 5 and 6.

FIG. 5 illustrates a relationship between the vehicle V traveling in theLKAS mode and a road. In FIG. 5, the ECU 20 of the vehicle V detectsboundary lines 201 and 202 of a lane on the basis of the images from thecameras 31A and 31B supplied from the ECU 21. Then, the ECU 20sequentially calculates and updates a path passing through the center ofthe boundary lines 201 and 202 as a target path 210 (S205). Then, theECU 20 causes the vehicle V to move along the target path 210 (S206).For example, the vehicle V keeps a current state while traveling withina predetermined allowable range centered on the target path 210. In acase where the vehicle V deviates to the right, for example, beyond theallowable range, the ECU 20 causes the ECU 22 to control steeringaccording to the deviation amount and the vehicle speed, thereby keepingtraveling along the target path 210.

In a case where the driver operates the blinker lever 51 or 52 orperforms an operation to turn off the LKAS mode via the input device 45during traveling in the LKAS mode, the ECU 20 transitions from the LKASmode to the manual driving mode. Meanwhile, in a case where the driveroperates the steering wheel ST without operating the blinker lever 51 or52 and the vehicle V approaches the boundary line 202 beyond theallowable range, for example, as illustrated in FIG. 6, the ECU 20 warnsthe driver via a notification unit such as sound, display, and vibration(S203) and causes the ECU 22 to guide the vehicle V within the allowablerange. Then, in a case where the driver still performs an operation tocross the boundary line 202 without operating the blinker levers againstthe guidance, the LKAS mode transitions to the manual driving mode.

The above is the basic control processing in the LKAS mode by the ECU20. One of characteristics of the processing performed by the ECU 20 inthe present embodiment is that the processing in S208 and S209 isperformed during control in the LKAS mode. This will be described againwith reference to FIG. 5.

In a case where the ECU 20 can detect a boundary line 203 outside thelane in which the vehicle V is traveling while controlling the vehicle Vto travel along the target path 210 in the LKAS mode, the ECU 20determines that there is an adjacent lane (Yes in S208) and calculatesand updates a traveling path 211 passing through the center of theadjacent lane sandwiched between the boundary lines 202 and 203 in thatcase. The ECU 20 uses the traveling path 211 to avoid a collision at thetime of detecting an obstacle (e.g., a person). Hereinafter, processingof the ECU 20 at the time of detecting the obstacle will be described.

FIG. 3 is a flowchart showing the processing of the ECU 20 in a casewhere the ECU 20 detects an obstacle during traveling in the LKAS mode(in a case where the determination in S210 of FIG. 2 is Yes).

In S301, the ECU 20 starts collision avoidance assist processing mainlyincluding braking control. As a result, collision avoidance processingby deceleration or stop processing is started as necessary in the lanein which the vehicle is traveling. Note that processing described belowis performed in parallel to the collision avoidance assist processing.

In S302, the ECU 20 determines whether or not the adjacent lane hasalready been detected. Then, in S303, the ECU 20 determines whether toguide the vehicle to the path 211 in the adjacent lane. In theembodiment, a probability value of collision avoidance with the obstacleonly by braking and steering control in the lane in which the vehicle Vis currently traveling is calculated on the basis of a traveling speedof the vehicle V and positions of the vehicle V and the obstacle and adistance therebetween in the lane in which the vehicle V is traveling.Then, in a case where the calculated probability value is equal to orless than a predetermined threshold (in a case where there is a highprobability of collision in the current lane), the ECU 20 determines toguide the vehicle to the adjacent lane.

In a case where the ECU 20 determines to guide the vehicle to theadjacent lane, the ECU 20 advances the processing to S304. In S304, theECU 20 calculates a connection path (hereinafter, referred to as atransition path) to the path 211 in the adjacent lane on the basis of acurrent positional relationship between the vehicle V and the obstacleand the traveling speed of the vehicle.

A line segment 700 in FIG. 7 is the transition path calculated in S304.The transition path 700 is a gentle curve with respect to both thetarget path 210 through which the vehicle is currently traveling and thepath 211 in the adjacent lane while avoiding the obstacle. A rangebetween allowable range paths 701 and 702, which indicates a range of adistance preset from the transition path 700, is an allowable range ofthe transition path 700.

In S305, the ECU 20 controls the ECU 25 to guide the vehicle to travelalong the transition path 700 (or within the allowable range of thetransition path). The word “guide” herein includes a steering wheelassist processing for causing the vehicle to travel along the transitionpath 700 and, in the embodiment, further includes processing forhighlighting (e.g., blinking in red) a symbol that intuitively promptsthe driver to move to the right lane, such as “>>”, on a screen andmaking a warning sound for calling attention.

Herein, the processing in S305 will be described in more detail.

The vehicle V travels on the left side of the allowable range path 701of the transition path 700 in FIG. 7, travels between the allowablerange paths 701 and 702, or travels on the right side of the allowablerange path 702 during this guidance. In a case where the ECU 20 of theembodiment determines that the vehicle is traveling on the left side ofthe allowable range path 701 of the transition path 700, the ECU 20determines that an operation amount of the steering wheel ST forcollision avoidance with an obstacle 500 by the driver is deficient,obtains a steering amount that compensates for the deficiency of theoperation amount, performs steering control in accordance with theobtained steering amount, and guides the vehicle so that the vehicleenters the adjacent lane.

Meanwhile, the ECU 20 of the embodiment travels on the right side of theallowable range path 702 of the transition path 700 in a case where thedriver excessively operates the steering wheel ST in order to avoid acollision with the obstacle 500. An entry angle with respect to theadjacent lane is excessively increased, and the vehicle may reach theboundary line 203 of the adjacent lane depending on the vehicle speed.In a case where some object such as a wall exists on the boundary line203, there is a possibility of a secondary collision with the objectexisting in the vicinity of the boundary line 203. Therefore, in thepresent embodiment, in a case where the vehicle V travels on the rightside of the allowable range path 702 of the transition path 700 due tothe excessive operation of the steering wheel ST by the driver, the ECU20 performs steering control to reduce the entry angle with respect tothe adjacent lane.

In S306, the ECU 20 determines whether or not the vehicle has enteredthe adjacent lane beyond the boundary line 202. Note that thedetermination on entry into the adjacent lane is made by determiningwhether or not a preset position of the vehicle V (e.g., one front wheelor a front corner position of the vehicle) has reached the boundary lineof the adjacent lane.

When the entry into the adjacent lane is detected, in S307, the ECU 20determines that the guidance to the adjacent lane has been approved bythe driver and controls the ECU 25 to notify the driver that processingfor switching lanes is started. For example, a message or the likeindicating that the vehicle is transitioning to the adjacent lane isdisplayed. Instead of (or in addition to) the display of the message, asound indicating that authentication of movement to the adjacent lanehas been confirmed may be output. Then, in S308, the ECU 20 sets thepath 211 calculated in the latest S209 as a new target path whilekeeping an on state of the LKAS mode.

After entering the adjacent lane, the vehicle V at that time is notnecessarily traveling along the transition path 700. Even at this stage,the driver may excessively operate the steering wheel ST at the time offinding the obstacle. In a case where the steering wheel ST isexcessively operated, the vehicle may move to the boundary line 203depending on the speed at that time as indicated by a reference sign 710in FIG. 7. In a case where an obstacle happens to exist at that positionon the boundary line 203, a secondary collision may even occur.

Therefore, in the present embodiment, stronger steering assist controlis started in S309 in a period until the vehicle normally travels alongthe path 211. Then, the assist processing in S309 continues until it isdetermined in S310 that the vehicle stably travels along the travelingpath 211.

The assist processing in S309 will be described below.

In a case where the vehicle V is traveling along the transition path700, the vehicle V only needs to keep the traveling state. The travelingalong the transition path 700 in this case is that the vehicle travelswhile simultaneously satisfying the following conditions. A firstcondition is that the vehicle travels within the range between theallowable range paths 701 and 702 of the transition path 700. A secondcondition is that an angle between a tangential direction at a pointcorresponding to the position of the vehicle V on a coordinate axisorthogonal to the path 211 on the transition path 700 and a travelingdirection of the vehicle V is equal to or less than a preset threshold.

In a case where at least one of the above conditions is not satisfied,the ECU 20 in the embodiment determines that it is impossible to travelalong the transition path 700. For example, this is a case where thedriver excessively operates the steering wheel ST. In this case, insteadof performing traveling control on the transition path 700, the ECU 20switches to steering assist processing for smoothly transitioning to thepath 211 without reaching the boundary line 203. The steering assistprocessing in this case will be described with reference to FIGS. 8A and8B.

FIG. 8A illustrates a state in which the driver excessively turns thesteering wheel ST and the vehicle V enters the adjacent lane. In FIG.8A, a center position of both the front wheels is represented by areference sign 800, and a line segment 801 indicates a travelingdirection of the vehicle V. The symbols θ and d are defined as follows.

The symbol θ represents an angle between the traveling direction 801 ofthe vehicle V and (an extension line of) the path 211. The symbol drepresents a distance between the vehicle V and the extension line ofthe path 211. The distance d is defined as having a positive value onthe left side of the path 211 serving as an origin and a negative valueon the right side thereof. Further, although not illustrated, thevehicle speed of the vehicle V is defined as v.

In this case, it is obvious that the possibility that the vehicle Vmoves to the position of the boundary line 203 increases as the vehiclespeed v increases, as the distance d decreases (as the negative absolutevalue increases), and as the angle increases (up to 90 degrees). Forexample, even in a case where the vehicle speed v and the angle θ inFIG. 8B are the same as those in FIG. 8A, the possibility that thevehicle V moves to the boundary line 203 is much higher in FIG. 8B thanin FIG. 8A. That is, a control amount for controlling steering so as toprevent the vehicle V from positioning on the boundary line 203 can beobtained by a function f (θ, d, v) including those three parameters θ,d, and v as arguments.

FIG. 4 is a flowchart showing details of the assist processing in S309of FIG. 3. Hereinafter, processing of the ECU 20 will be described withreference to FIG. 4.

In S401, the ECU 20 determines whether or not the vehicle V is travelingalong the transition path 700. Determination conditions for determiningwhether or not the vehicle is traveling along the transition path 700are as described above. In a case where the determination in S401 isYes, the ECU 20 does not perform the following processing and advancesthe processing to S310 in FIG. 3.

In a case where the determination in S401 is No, that is, in a casewhere the vehicle V is not traveling along the transition path 700, theECU 20 advances the processing to S402.

In S402, the ECU 20 acquires the vehicle speed v via the ECU 27 andcalculates the entry angle θ of the vehicle V with respect to the targetpath 211 and the distance d between the target path 211 and the vehicleVon the basis of the information of the ECU 21 and the like.

Next, in S403, the ECU 20 obtains a steering control amount for avoidingreaching the boundary line 203 in accordance with a function prepared inadvance on the basis of the vehicle speed v, the angle θ, and thedistance d. Note that the time related to the calculation can be ignoredby using a lookup table to which v, θ, and d are input, instead ofcalculating the control amount.

Then, in S404, the ECU 20 controls the ECU 22 so as to achieve theobtained steering amount.

The above is the details of the processing in S309. The determination onwhether to terminate the assist processing in S310 of FIG. 3 is made ina case where the following two conditions 1 and 2 are simultaneouslysatisfied.

Condition 1: The distance d falls within an allowable range duringtraveling through a path in the LKAS mode.

Condition 2: The angle θ is equal to or less than a threshold.

According to the above description, in a case where the driver performsan operation to deviate from the allowable range (the range between thereference signs 701 and 702) of the transition path 700 while thevehicle V is traveling within the allowable range, the determination inS401 is No. That is, the ECU 20 switches a target from the transitionpath 700 to the traveling path 211. However, in a case where the driverperforms an operation of approaching the boundary of the allowable range(the range between the reference signs 701 and 702) while the vehicle istraveling within the allowable range of the transition path 700, the ECU20 may perform steering control to return to the transition path 700.

In the above description of FIG. 4, in a case where the vehicle V entersthe adjacent lane and a traveling position at that time deviates fromthe transition path, the ECU 20 performs steering control by using θ, v,and d as parameters. However, for example, in a case where an obstacle850 exists in the traveling direction in the state of FIG. 8A, the ECU20 may calculate a collision avoidance path in order to avoid asecondary collision therewith and issue, for example, a notification toprompt the driver to turn the steering wheel ST to the left inaccordance with the calculated collision avoidance path. In a case wherethe driver performs an operation to turn the steering wheel ST to theleft upon receipt of this notification, the ECU 20 may determine thatthe notification has been approved and start assist processing bysteering control of the steering wheel ST in the operation direction.Meanwhile, in a case where the collision avoidance path for the obstacle850 cannot be calculated, the ECU 20 may perform braking control.

FIG. 9 illustrates a movement path 900 of the vehicle V until thevehicle V travels along the path 211 in a case where the driverexcessively operates the steering wheel ST to avoid an obstacle. FIG. 9illustrates a case where a traveling path obtained when the driveroperates the steering wheel ST deviates from the transition path 700from the beginning. Even if, at the time of finding an obstacle, thedriver operates the steering wheel ST to deviate from the transitionpath 700 prepared by the system as illustrated in FIG. 9, it is possibleto perform steering control to smoothly transition to the path 211 whilepreventing the vehicle from reaching the boundary line 203 according tothe present embodiment.

In summary, in a case where the obstacle 500 appears in the travelingdirection during traveling along the target path 210 in the LKAS mode,whether to retreat to the adjacent lane is determined in the embodiment.Then, in a case where it is determined that it is desirable to switch tothe adjacent lane, the driver is prompted to travel along the transitionpath 700. Then, in a case where the driver actually performs anoperation to enter the adjacent lane, the EUC 20 determines that theswitching assist to the adjacent lane has been approved by the driverand switches to the traveling path 211 while keeping the on state of theLKAS mode. In the embodiment, it is possible to know that the system isperforming safe processing for collision avoidance and therefore gain asense of security. Further, even if the steering wheel is operated morethan necessary in order to avoid a collision with an obstacle, steeringcontrol stronger than the LKAS is performed at an early stage after thevehicle enters the adjacent lane. Therefore, it is possible to restraintraveling beyond the lane, and it is also possible to restrain thepossibility of a secondary collision.

Other Embodiments

In the above embodiment, the description has been made under thecondition that the vehicle travels while keeping the on state of theLKAS mode. Generally, in a case where the vehicle moves to the adjacentlane (changes lanes) without operating the blinker levers whiletraveling with the LKAS mode on, the LKAS mode is turned off. However,according to the above embodiment, in a case where the vehicle entersthe adjacent lane in order to avoid a collision with an obstacle, it ispossible to keep the on state of the LKAS mode in the adjacent lanewithout any special operation, which is advantageous. However, in a casewhere it is unnecessary to keep the LKAS before and after switchingtraveling lanes, the condition that the vehicle is traveling with theLKAS mode on may be excluded in the processing related to collisionavoidance with an obstacle described in the above embodiment. In thiscase, it is only necessary to determine that steering control in theadjacent lane has been approved by the driver on the condition that avalue indicating the probability of collision avoidance with an obstacleis smaller than the threshold and the vehicle has entered the adjacentlane in response to steering of the steering wheel ST by the driver(there is no condition regarding the LKAS mode).

Further, the path 211 passing through the center of the adjacent lane isset as a traveling path when the transition to the adjacent lane iscompleted. However, in a case where the LKAS mode is not required, aposition of the path after the transition is completed is notparticularly limited as long as the path can avoid a collision with aninitial obstacle.

In the above embodiment, the description has been made on the assumptionthat there is no other vehicle traveling in the adjacent lane. However,in a case where there is some object in the adjacent lane and it isestimated that a distance between the object and the vehicle V is equalto or less than a preset distance, guidance to the adjacent lane may notbe performed.

Specifically, for example, in a case where the adjacent lane is apassing lane, a step of determining whether or not another vehicletraveling within a predetermined distance behind the self-vehicle in thepassing lane has been detected (which can be detected by the radar 32B)may be provided immediately after S303 in FIG. 3. Then, in a case wherea result of the determination shows that no vehicle exists, theprocessing may proceed to S304. In a case where the adjacent lane is anoncoming lane, a step of determining whether or not there is anothervehicle coming from the front within a predetermined distance (which canbe detected by the camera 32A) may be provided immediately after S303 inFIG. 3. Then, in a case where a result of the determination shows thatno vehicle exists, the processing may proceed to S304. In a case wherethe vehicle safely travels in both cases where the adjacent lane is apassing lane and an oncoming lane, the above two determinations may besuccessively provided immediately after S303. Then, in a case whereresults of both the determinations show that no vehicle exists, theprocessing may proceed to S304.

Note that whether or not the lane is a passing lane or oncoming lane maybe determined on the basis of information (the current position of thevehicle V and information of a navigation system) from the ECU 28.

In the above embodiment, the description has been made on the assumptionthat braking control is performed in S301 when an obstacle is found.However, the braking control may be executed in a case where it isdetermined that the vehicle does not retreat to the adjacent lane, in acase where the determination in S302 is No, or in a case where thedetermination in S303 is No.

In the embodiment, a target to be used for collision avoidance with anobstacle is an adjacent lane. However, the present invention is notlimited thereto. For example, the target may be a certain degree ofvacant land such as a shoulder.

Summary of Embodiments

The above embodiments disclose at least the following embodiments.

1. According to the above embodiments, there is provided a vehiclecontrol device for controlling a vehicle, which comprises:

a first detection unit configured to detect an out-of-lane regionoutside a lane in which the vehicle is traveling;

a second detection unit configured to detect an obstacle;

a guiding unit configured to start guiding the vehicle to theout-of-lane region in a case where the first detection unit detects theout-of-lane region and the second detection unit detects the obstacle;and

a steering control unit configured to determine excess or deficiency ofavoidance steering by a driver for avoiding a collision with theobstacle in response to the guidance by the guiding unit and performsteering assist on the basis of a degree of the excess or deficiency.

According to this embodiment, it can be expected that the vehicle stablytravels in the out-of-lane region while avoiding a collision with theobstacle by using the out-of-lane region. In the above, the performingof steering control is a control to assist the steering.

2. According to the above embodiments, the guiding unit calculates avalue indicating a probability of avoiding the collision with theobstacle in a situation where the vehicle travels in the lane in whichthe vehicle is traveling and, in a case where the value is equal to orless than a predetermined value, starts guiding the vehicle to theout-of-lane region.

As a result, the driver can know that the collision with the obstaclecan be avoided by performing a steering operation in accordance with theguidance. This makes it possible to give a sense of security.

3. According to the above embodiments, the guiding unit

calculates a path for entering the out-of-lane region to avoid thecollision with the obstacle, and

determines the excess or deficiency of the avoidance steering inaccordance with a position of the vehicle with respect to the path.

According to this embodiment, it is possible to accurately determine theexcess or deficiency of the avoidance steering.

4. According to the above embodiments, the steering control unitperforms the steering assist for avoiding the collision with theobstacle in a case where the steering control unit determines that asteering operation by the driver is deficient.

According to this embodiment, it is possible to further improve thecollision avoidance with the obstacle.

5. According to the above embodiments, the steering control unitdetermines that a steering operation by the driver is excessive in acase where the vehicle is predicted to reach a boundary of theout-of-lane region.

According to this embodiment, it is possible to perform steering controlat an early stage on the assumption that an object such as a wall existsat a boundary of the out-of-lane region.

6. According to the above embodiments, the vehicle control devicefurther comprises

a braking control unit configured to perform braking control foravoiding the collision with the obstacle when the guiding unit startsthe guidance.

According to this embodiment, it is also possible to perform thecollision avoidance by using braking control processing.

7. According to the above embodiments, the vehicle control devicefurther comprises

a braking control unit configured to perform braking control in the lanein a case where entry into the out-of-lane region is not approved by thedriver after the obstacle is detected and the guidance to theout-of-lane region is performed.

According to this embodiment, it is possible to perform collisionavoidance processing by braking control even in a case where the vehiclecontinuously travels in the lane.

8. According to the above embodiments, the guiding unit restrictsperforming the guidance of the vehicle to the out-of-lane region in acase where, when the vehicle enters the out-of-lane region and travelsafter the obstacle is detected, the vehicle is predicted to come intocontact with another object in the out-of-lane region. For example, theguiding unit does not guide the vehicle to the out-of-lane region in acase where, when the vehicle enters the out-of-lane region and travelsafter the obstacle is detected, the vehicle is predicted to come intocontact with another object in the out-of-lane region.

According to this embodiment, it is possible to prevent a collision withthe another object in the out-of-lane region in advance.

9. According to the above embodiments, the guiding unit includes anotification unit configured to notify the driver by using display of asymbol indicating a direction of a steering operation and a warningsound during a period in which the guiding unit guides the vehicle tothe out-of-lane region.

According to this embodiment, it is possible to prompt the driver toperform the steering operation toward the out-of-lane region.

10. According to the above embodiment, there is provided a vehicleincluding the vehicle control device having any of the aboveconfigurations is provided. As a result, the vehicle can have thefunctions and effects described above.

11. According to the above embodiments, there is provided a method ofcontrolling a vehicle control device for controlling a vehicle, whichcomprises:

detecting an out-of-lane region outside a lane in which the vehicle istraveling;

detecting an obstacle;

starting guiding the vehicle to the out-of-lane region in a case wherethe out-of-lane region is detected in the detecting the out-of-laneregion and the obstacle is detected in the detecting the obstacle; and

determining excess or deficiency of avoidance steering by a driver foravoiding a collision with the obstacle in response to the guidance bythe starting guiding and perform steering assist on the basis of adegree of the excess or deficiency.

According to this embodiment, it can be expected that the vehicle stablytravels in the out-of-lane region while avoiding a collision with theobstacle by using the out-of-lane region.

12. According to the above embodiments, there is provided anon-transitory computer-readable storage medium storing a program to beread and executed by a processor included in a vehicle control devicefor controlling a vehicle, the program causing the processor to execute:

detecting an out-of-lane region outside a lane in which the vehicle istraveling;

detecting an obstacle;

starting guiding the vehicle to the out-of-lane region in a case wherethe out-of-lane region is detected in the detecting the out-of-laneregion and the obstacle is detected in the detecting the obstacle; and

determining excess or deficiency of avoidance steering by a driver foravoiding a collision with the obstacle in response to the guidance bythe starting guiding and perform steering assist on the basis of adegree of the excess or deficiency.

According to this embodiment, in a case where the program for performingthose steps is set to a target to be executed by the processor (e.g.,ECU) of the vehicle control device, it can be expected that the vehiclestably travels in the out-of-lane region while avoiding the collisionwith the obstacle by using the out-of-lane region.

The invention is not limited to the foregoing embodiments, and variousvariations/changes are possible within the spirit of the invention.

What is claimed is:
 1. A vehicle control device for controlling avehicle, the vehicle control device comprising: a first detection unitconfigured to detect an out-of-lane region outside a lane in which thevehicle is traveling; a second detection unit configured to detect anobstacle; a guiding unit configured to start guiding the vehicle to theout-of-lane region in a case where the first detection unit detects theout-of-lane region and the second detection unit detects the obstacle;and a steering control unit configured to determine excess or deficiencyof avoidance steering by a driver for avoiding a collision with theobstacle in response to the guidance by the guiding unit and performsteering assist on the basis of a degree of the excess or deficiency. 2.The vehicle control device according to claim 1, wherein the guidingunit calculates a value indicating a probability of avoiding thecollision with the obstacle in a situation where the vehicle travels inthe lane in which the vehicle is traveling and, in a case where thevalue is equal to or less than a predetermined value, starts guiding thevehicle to the out-of-lane region.
 3. The vehicle control deviceaccording to claim 1, wherein the guiding unit calculates a path forentering the out-of-lane region to avoid the collision with theobstacle, and determines the excess or deficiency of the avoidancesteering in accordance with a position of the vehicle with respect tothe path.
 4. The vehicle control device according to claim 1, whereinthe steering control unit performs the steering assist for avoiding thecollision with the obstacle in a case where the steering control unitdetermines that a steering operation by the driver is deficient.
 5. Thevehicle control device according to claim 1, wherein the steeringcontrol unit determines that a steering operation by the driver isexcessive in a case where the vehicle is predicted to reach a boundaryof the out-of-lane region.
 6. The vehicle control device according toclaim 1, further comprising a braking control unit configured to performbraking control for avoiding the collision with the obstacle when theguiding unit starts the guidance.
 7. The vehicle control deviceaccording to claim 1, further comprising a braking control unitconfigured to perform braking control in the lane in a case where entryinto the out-of-lane region is not approved by the driver after theobstacle is detected and the guidance to the out-of-lane region isperformed.
 8. The vehicle control device according to claim 1, whereinthe guiding unit restricts performing the guidance of the vehicle to theout-of-lane region in a case where, when the vehicle enters theout-of-lane region and travels after the obstacle is detected, thevehicle is predicted to come into contact with another object in theout-of-lane region.
 9. The vehicle control device according to claim 1,wherein the guiding unit includes a notification unit configured tonotify the driver by using display of a symbol indicating a direction ofa steering operation and a warning sound during a period in which theguiding unit guides the vehicle to the out-of-lane region.
 10. A vehicleincluding a vehicle control device, wherein the vehicle control deviceincludes a first detection unit configured to detect an out-of-laneregion outside a lane in which the vehicle is traveling, a seconddetection unit configured to detect an obstacle, a guiding unitconfigured to start guiding the vehicle to the out-of-lane region in acase where the first detection unit detects the out-of-lane region andthe second detection unit detects the obstacle, and a steering controlunit configured to determine excess or deficiency of avoidance steeringby the driver for avoiding a collision with the obstacle in response tothe guidance by the guiding unit and perform steering assist on thebasis of a degree of the excess or deficiency.
 11. A method ofcontrolling a vehicle control device for controlling a vehicle, themethod comprising: detecting an out-of-lane region outside a lane inwhich the vehicle is traveling; detecting an obstacle; starting guidingthe vehicle to the out-of-lane region in a case where the out-of-laneregion is detected in the detecting the out-of-lane region and theobstacle is detected in the detecting the obstacle; and determiningexcess or deficiency of avoidance steering by a driver for avoiding acollision with the obstacle in response to the guidance by the startingguiding and perform steering assist on the basis of a degree of theexcess or deficiency.
 12. A non-transitory computer-readable storagemedium storing a program to be read and executed by a processor includedin a vehicle control device for controlling a vehicle, the programcausing the processor to execute: detecting an out-of-lane regionoutside a lane in which the vehicle is traveling; detecting an obstacle;starting guiding the vehicle to the out-of-lane region in a case wherethe out-of-lane region is detected in the detecting the out-of-laneregion and the obstacle is detected in the detecting the obstacle; anddetermining excess or deficiency of avoidance steering by a driver foravoiding a collision with the obstacle in response to the guidance bythe starting guiding and perform steering assist on the basis of adegree of the excess or deficiency.